Q. R. Chanina (S’gan HaCohanim) said that he saw the heavenly fire descend (on the altar) resembling a crouching dog in the second temple (Yoma 21b). Is there any commentary on what that means? Why compare the Heavenly Holy fire to a crouching dog!?
A. A number of reasons and explanations are offered, I’ll quote just a few. Maharsho (ibid.) explains that the first Beis Hamikdosh was built by Shlomo Hamelech, a descendant of Yehuda represented by the symbol of a lion. However, the second Beis Hamikdosh was erected with the blessings of the Persian Empire, compared to a dog as in Nehemia 2: 6.
Iyun Yaakov mentions that during the first Beis Hamikdosh, the Shechina ruled and was openly present for all to see, as the posuk (Amos 3: 8) compares it to; ‘A lion that when he roars, who will not be afraid,’ not so during the Second Temple, the presence of the Shechina was diminished, giving place to the tumah or impurity compared to a dog to show itself.
Kaftor Vaferach maintains that the presence of the Shechina’s Heavenly Fire, depends on the people present to receive it. During the first Beis Hamikdosh, there were far many more great Tzadikim and holy Sages forthcoming and available. Not so during the Second Temple. That penurious stage was compared to a dog, on whom our sages teach, since his food is scarce, Hashem made his needs little and so requires small amounts of food to survive.
Rabbi A. Bartfeld as revised by Horav Aharon Miller Shlit’a